• Miles of uncrowded white sandy beaches extend to the horizon, separating the clear blue ocean and undulating grass-covered dunes.

    Fire Island

    National Seashore New York

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  • Pet Restrictions in Effect March 15 through Labor Day

    Dogs/other pets (except for service animals) are not allowed in the wilderness or on any of Fire Island's federally owned oceanfront beaches from March 15 through Labor Day to help protect threatened and endangered beach-nesting shorebirds. More »

  • Backcountry Camping Permit and Access Procedures

    Reservations for required permits must be obtained through www.recreation.gov. Due to the breach at Old Inlet, access to both east and west wilderness camping zones must now be from Watch Hill or points west, and involve a 1½ to 8 mile hike. More »

  • Attention Watch Hill Ferry Passengers

    Due to channel conditions, delay or cancellation of ferry service between Patchogue and Watch Hill may occur. For updated ferry schedule information, please call 631-475-1665.

Horseshoe Crabs

Horseshoe crabs spawn on bay beaches

Despite its common name, the horseshoe crab (Limulus polyphemus), is more closely related to spiders and scorpions than crabs. All are invertebrates from the phylum Arthropoda, or arthropods. This group of animals includes insects (Insecta); spiders, scorpions, ticks and mites (Arachnida, or arachnids); crabs, lobsters, shrimp and barnacles (Crustacea, or crustaceans); and the 4 world-wide species of horseshoe crabs (Merostomata).

Horseshoe crabs are an ancient species. For over 300 million years (at least 100 million years before there were dinosaurs on earth) horseshoe crabs have roamed the world's oceans and and look today much as they have through the millennia.

Learn more about the natural history of horseshoe crabs.



Fun Horseshoe Crab Facts
Did you know that horseshoe crabs have blue blood? The protein (hemocyanin) that carries oxygen in horseshoe crab blood contains copper. When oxygen binds to the copper, the blood turns blue. As the oxygen is removed from the copper (as the blood circulates and delivers oxygen to the tissues of the horseshoe crab) the blood becomes colorless. The protein (hemoglobin) that carries oxygen in human blood contains iron. When oxygen is bound to the iron, human blood is red. As the oxygen is removed from the iron, the blood becomes blue.

The name horseshoe crab refers to the shape of the animal. The front half of a horseshoe crab looks like a horse's hoof or a horseshoe.


Learn More

  • Horseshoe Crab: History & Biology/Shorebird Connection/Human Use/Research/Fisheries Management
  • Horseshoe Crab New York State Fishery and Regulations
    New York State Department of Environmental Conservation
    (Fire Island National Seashore is one of the areas now closed to the harvest of horseshoe crabs in New York)

Did You Know?

PWC passes a green channel marker in bay near wooded shoreline and salt marsh.

The use of personal watercraft (PWCs or JetSkis) is restricted within the boundaries of Fire Island National Seashore. While not permitted at National Park Service facilities or near shorelines, PWCs may use the marked channels to access some of the Fire Island communities. More...